Chantal le Clercq

Interval Colorectal Cancers: What and Why

An increasing number of studies now indicate that colonoscopic examination is not perfect in preventing colorectal cancer (CRC), especially of the proximal colon. Several factors can be implicated in the occurrence of interval CRCs—further referred to as postcolonoscopy CRCs-, such as missed, incompletely resected lesions and newly developed cancers. Missed lesions represent by far the dominant cause of postcolonoscopy CRCs, with nonpolypoid (flat or depressed) neoplasms and sessile serrated polyps playing a significant role. Molecular events underlying progression of such lesions may further augment the cancer risk. In this article, we review the literature about postcolonoscopy CRC risk and the most common explanations. We discuss potential implications, paying special attention to improvements required in education and training.

Understanding the Biologic Behavior of Sessile Serrated Adenomas/Polyps

To the Editor: With great interest we read the recent article by Tinmouth et al. (1) in this Journal, adding evidence on the importance of accurate detection, classification, and complete endoscopic resection of sessile serrated adenomas/polyps (SSAs/Ps) to avoid the occurrence of post-colonoscopy colorectal cancers (PCCRCs). The biologic behavior of SSAs/Ps is sparsely understood. Here, we present the case of a patient who developed a PCCRC 4 years after a colonoscopy with removal of a SSA/P with dysplasia.

Tu1163 Macroscopic Features of Neuroendocrine Colorectal Cancers: A 10-Year Retrospective Study

vs. jejunum 90% vs. ileum 93%, p< 0.001). There was no significant difference in mean age at diagnosis, sex, or the number of additional primary cancers between the three primary sites. Using KM methods, five-year survival was marginally better for duodenal and ileal lesions than jejunal lesions (duodenum 67% vs. jejunum 66% vs. ileum 61%, p=0.045). However, on CPH analysis, duodenal lesions had significantly better survival than jejunal or ileal lesions (jejunum vs. duodenumHR 1.845 [95% CI 1.461-2.329] p<0.001, ileum vs. duodenal HR 1.665 [95% CI 1.388-1.999], p<0.001), controlling for age, stage, year of diagnosis, sex, race, marital status, and cancer-directed surgery. Conclusion: Epidemiology and survival patterns of SICs vary based on intestinal location. As duodenal lesions are diagnosed at an earlier stage and associated with significantly improved survival than jejunal or ileal lesions, it may be possible to avoid high-risk surgery for selected lesions in these patients.